Vertical Redistribution of Halogenated Very Short-Lived Substances by Midlatitude Convective Storms During the DC3 Field Campaign

Abstract:

Halogenated very short-lived substances (VSLS) can play an important role in both tropospheric and stratospheric chemistry. The impact of halogenated VSLS on halogen loading in the upper troposphere and lower stratosphere (UT/LS) is uncertain, and their potential impacts on stratospheric ozone loss are not well-quantified. Slow, large-scale ascent of tropospheric air into the stratosphere occurs primarily in the tropics, but large midlatitude convective storms have been shown to rapidly transport tropospheric air into the stratosphere during summer months. In this work, data from the Deep Convective Clouds and Chemistry field campaign (DC3, summer 2012) is used to investigate vertical redistribution of halogenated VSLS from the planetary boundary layer (PBL) into the UT/LS region. UC Irvine's whole air sampler (WAS) was deployed onboard the NASA DC-8, and measured a suite of halogenated species including many halogenated VSLS. Using these measurements, the fractional contribution of each halogen species to the total halogen loading will be calculated for airmasses in the PBL, UT, and LS. Total halogen loading will be compared between UT/LS airmasses that have not been affected by convection and airmasses that have been affected by recent convection, and the impact of halogenated VSLS from the PBL on total halogen loading will be quantified. This will allow futher work to be done to assess the role of midlatitude convective storms on the chemistry and composition of the UT/LS region.